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WED A E OFFICE- 301m n. wires, or NEW Yonx, ain) cEARLEs 3.. Downs, oE cmrrsmn, nnw JERSEY, assrenons are THE BARRETT comm, n coaroaarrou or rmw J EsEr.

No Drawing.

To all it concern {Bait known that we, (1) JOHN M-.2WE1s s and (2) CHARLES R. Downs, citizens of the' United States, residing at (1) 210 West 110th none, etc. y

-We have obtained very satisfactory results by first mixing or dissolving thequinone inbcnzene (benzolm C 11,) and therestreet and (2) Clifi'side,'in the counties of (1) New York and (2) Bergen and-States of (1) New York and (2) New Jersey, have.

ments in the Production of Maleic cid, of

invented certain newand useful-Zg provewhich the following is a specificati j This invention relates to the oxidation of aromatic hydrocarbons or their derivatives whereby compounds of the' straight chain or aliphatic series may be obtained.

More particularly our invention has for one of its o'b ects the partial oxidation of a (ii-substitution product of a compound 7 containing the benzene-ring o'rnucleus in duced inany suitable way, for example, n accordance .with the process set forth insame througha heated region such as the interior of hollow tu'b'es which contains a. f proper catalyzer such as, for example, va-

the presence of a suitable catalyzer. I

While our invention may be carried out with, diiferent compounds it will be specifi cally described in its. operation as applied to the partial oxidation of quinone in the presence of a-catalyzer for the purpose of forming maleic acid and formaldehyde.

We may form an intimate mixture of oxygen and of quinone' (which has been prpour coending application Serial No. 236,839 led 'Mav 27, 1918, and pass the nadium oxid, or other compounds of vana- "dium. -The temperature should -be mainpregnate with 'the'c'atalyzer in order togromote'proper contact. The oxygen maytained at about 300 C; to 700 C., and the pressure may vary from a partial vacuum to a pressure far above atmospher1c,.say up to fiveatmospheres or more, while the mlxture isin contact with the catalyzer. The

mixture maybe injected intothe heated space in the form of vapor or may be sprayed therein, while the said'space contains pumice or other orous material which may be ime inthe pure state or may be oxygen'of the air, or mavfbe'diluted with nitrogen'or other inactivediluents'gwhich will exert a blanketing eflect toassist in limitingior controlling the oxidation, and in preventing complete oxidation to the point of combustion,

The conditions 'under-whieh'tlie desired reactions take place may .be varied, as by changing the length of-tinieduring which-J rnonuc'rron 0E MALEIC acm.

Specification of Letters Patent, Application filed May 27,1918, Serial RO. zaaaoo.

water.

the mixture isin transit through-the reaction chamber, changing the temperature and pressure, varyii'ig" the amountsof oxygen and the'dilucnts in proportion to the-quiafter introducing this. mixture or solution wlth a r into the reaction chamber and subsequently condensing the resulting prodstood as limiting our process to any particu' lar theory as to the reaction which takes place, it seems .from the results which we have obtained that probably the quinone already present ,is partially and selectively oxidized to form maleieacid and formaldehyde, while a portion of the benzene is also partially and selectively oxidized to produce 'a corresponding amount of quinone, and another portion of benzene is further oxidized out and be thus removed, or it may be removed by shaking the condensate with After the maleic acid'has been re Patented Oct. 14, 1919.

"ucts. Whilewe do not wish to be under-- moved, and also other products if necessary,

the residual benzene-quinone solution is passed again with more benzene and oxygen through 1 the reaction; chamber in, contact vwith the catalyzer whereby more maleic acid is formed as above indicated without materially increasing the amount of quinone' present.-

aid in preventing a. complete oxidation to It is, of course, obvious that the diluent gases present during the reaction, (and which may exert a blanketing influence to the'point of combustion), will notbe condensed, solar as they may he of a non-com: densable character, but-will pass oii'in a gaseous state,'while the condensable, products are-condensed and collected.

2 From the foregoing 'description'it will be noted that the process of the present inven- 't'ionfmay be considered; from-one aspect, as

' a processof effecting a partial and selective oxidation of quinone to compounds of the t aliphatic -'series 1.suchias-maleic raci'd and for-F.

ehy'de,"=while" ffrom-eanotheraspect{the i y I red lyap riby treating-it, when-l-an oxygen a: combination .Iprocess for eiterating asimul-y a ltaneous. oxidation-f xquinone to;.La1iphatic:

' compounds and-the catalytic oxidationflof benzene tozquinone-or part .toquinone 'andf Y 10' .frombeiizene during --;the'.-.:same; procedure i svaponphasegeby; treating it with an;=oxygen ----.contai'n ing- --gas :at ;-a-..;temperature between 2 3009 C. and "7 00 .f-C. the Lprese'ncez of -'vanadium-oxid--as;a catalyst so that.,.maleic whic theoxidatiombi quinone -to -....-a1iphd;ic compounds; It will :be noted false-that :the process of the resent invention can, withadvantage,

- 15,-.be ;practised asa cyclic process withesepara p --tion:;;andreti1rn .--of the-unchanged= benzene andquinone to be further acted onyin the .mannerabove described.

'zwhat'l-claim at ilhe herein desciibedprocess 'f pressure and in the oxid as a catalyst so t at maleic acid is produced, and recovering maleic acid from the products of reaction.

3.\The. herein described process of oxidizing guinone in the vapor phase by treating it with an'oxygen containing gas at a tem'. perature between 3009 C. and 700 C. and ,at 'such a t such a cata yst that maleic acid is produced, and recovering maleic acid from the prod 40 nets of reaction. a 4. The herein described process of oxidizing quinone in the vapor phaseby ftreating it with an'oxygen containing gas at a tem-.

perature between 300? and'700 C; the presence'of vanadium oxid as a" catalyst so -that maleic acid is produced, and recovering maleic acid fromthe products of reaction...

5. The herein describedprocess of oxidizing a mixture of benzene and quinone, in the vapor phase by an oxygenco'nta'ining gas at such a temperature andpressure and in the presenceof such a catalyst that maleic acid is produced, and recovering maleic acid from the products of reaction.

6. .The herein described processof oxidizing a mixture of benzene and quinone in the vapor phase by an-oxygen containing gas atsucha temperature and pressureand. in i that maleicacid-is produced, and recovering maleic acid from the pr'oducts'of reaction.

ymaleic aci r=z maleiccacidkfrpm:the roducts oi'reafition.

7 8: iThei-herem descri d' process .oifoxidizsas dsi e d -fromthe products of reaction.

I a of. benzene and guinoneiiirthe 14w mqfi et w h-sn ys ontaining .a; temperature-land presence of vanadiumressure and inthe presence of containing the presence of vanadium oxid as a catalyst so "ing amixture cr -benzene andq iinone in the containmgrz-gas .-at .-,a temperature between ing a mixture cfabenzeneand quinone in the eed-,a;and recovering maleic -acid 9. The herein described offoiidia vapor phase by containing gas at i;'7.QThe-herein-.described. process of'toxidiz ZOO G; and ;at such. a pressure I dthegmesence of. such, a .catalyst "that .-':produced, and "recovering Y 1 =i ng-'quinone in theyap'orsphasebyranpxyge ind inr'fliecfjfllchrqarcata- -v'con e mg f s-a c azztemp emfsa i p a inthe of suchacata-Ff 'thejnaleicacidhndsub .LhQIQSide-s F-"JSj't-thatmfleicacid sproduced,andrecovertand'guinone tofiu er z,'zs:- n'g .t eleieacidiromtheproductscf-reaction. -pigidationtoienniurther-amountsof maleic ;%processofoxidiz-- acid.

' mg qumoneinthe vapor phase by'an oxygen 10.. The herein described process of oxidizcontaining gas at such a temperature and ing a mixture of benzene and'quinone in the treating it with an oxygen such a temperature and 9 pressure and inthe resence of vanadium oxid as a catalyst so t at maleic acid is produced,'separatmg the maleic acid and sub footing the residual benzene and quinone to further similar oxidation to form further amounts o fmaleic acid.

11. The herein described ,process ing a mixture of benzene and quinone in the vapor phase by treating it with an oxygen s at a temperature between 300 (land 700 C. and at such' a pressure and in'the resence'of such a catalyst that. maleic aci is produced, separating the maleic acid and subjectin the residual benzene and quinone to furt er similaroxidation'to'form further amounts of maleic acid. 12.-'The herein described process" of oxidizing a miiiture of 'benzene and quinone in the vapor phase by treating it with an oxygen containing gas at "a temperature between 300 (land-700 C. and at such a pressure and in the presence of vanadium oxid as a catalyst so that maleic acid is produced, separating thev maleic acid and subjecting the residual benzene and quinone to /further. similar oxidation'to form furtheri amounts of maleic acid. v

.In testimony whereof we aflix' our signatures.

JOHN M.'WEIS S. CHARLES R. DOWNS, 

